1. Field of the Invention
Embodiments of the present general inventive concept relate to an image forming apparatus including an optical sensor unit to inspect a visual image.
2. Description of the Related Art
An image forming apparatus forms an image on a printing medium according to an input signal. Examples of such an image forming apparatus include a printer, a copier, a facsimile machine, and a complex machine having functions of the above-mentioned appliances.
An electrophotographic image forming apparatus, which is a kind of image forming apparatus, includes a photosensitive body, an optical scanning unit, and a developing unit. The optical scanning unit scans light to the photosensitive body, which is charged with predetermined potential, to form an electrostatic latent image on the surface of the photosensitive body, and the developing device supplies a developing agent to the photosensitive body, on which the electrostatic latent image is formed, to form a visible image.
Toner used in the image forming apparatus generally has four colors, i.e., yellow (Y), magenta (M), cyan (C), and black (K), and four developing units are needed to fuse the toners of four colors on an electrostatic latent image.
In addition, such an image forming apparatus may include an optical sensor unit to inspect a developed visual image and a cleaning unit to clean toner accumulated on a light window of the optical sensor unit.